found: Catalogue of splendid and rare green and hot-house plants, 1839, viewed online Februrary 22, 2023:title page (M. Thomas & Son, auctioneers)
found: Worldcat searched February 22, 2023(access point: M. Thomas & Son; M. Thomas & Sons Auctioneers; Thomas & Son's Auction Store; usage: M. Thomas & Son; Thomas & Son; M. Thomas & Son's Auction Store; Thomas & Son's Auction Store)
found: Biographical encylopaedia of Pennsylvania, 1874, viewed online February 22, 2023(Thomas, Moses; publisher, bookseller, and auctioneer; born, Frankford, Philadelphia County, 1787; died August 15, 1865; in 1828, with brother, founded auction and commission house, M. & S. Thomas, originally located at no. 87 Chestnut Street; after retirement of his brother, carried on business in the name of M. Thomas alone, succeeded by M. Thomas & Sons, two sons assuming responsibilities in the business; moved business to building on Fourth Street, below Chestnut)
found: Catalogue of books to be sold, 1825:t.p. (M. & S. Thomas; auctioneers at Philadelphia, Pa.)
found: Old SCIPIO authority file, accessed December 5, 2022(access point: M. Thomas & Sons' Galleries, Philadelphia; variant access points: M. & S. Thomas (1823); M. Thomas (1828-32); M. Thomas and Son (1836-47); years of operation: 1823-1906; place of sale: Philadelphia)